Farmers can grow more slow climate change

Two new studies have confirmed that farmers can win
both ways-achieving a boost in harvests and helping
to slow climate change, reports UNB.
One study says that they can successfully farm with
techniques that can help slow global warming and add
to the store of carbon sequestered in the soils
around the globe.
And a second study confirms that a range of tested
and sustainable practices is already stepping up
yields in small farms worldwide, while dramatically
reducing greenhouse gas emissions, soil erosion and
pesticide use, according to a message received from
Climate News Network.
Both studies address a planetary dilemma. Global
agriculture is at serious risk from global warming
and climate change driven by profligate fossil fuel
combustion.
But global agriculture - powered by greenhouse gas-
emitting fossil fuels, ploughing, pesticides and
herbicides - is also helping to drive global warming
and climate change.
And while researchers have persistently argued that
it should be possible both to feed the 9 billion
people expected by 2050, and to contain global
warming to no more than 2°C by 2100, such
advances can be achieved only by massive changes in
diet and expectations. But both new studies focus on
what is both practicable and possible right now.
US researchers report in the journal Science Advances
that they have identified a range of well-established
farming practices that - if adopted by everybody -
could capture enough carbon from the atmosphere and
store it in the world's soils at a rate that could
make a significant difference.
They suggest that simple approaches - cover crops,
more thoughtful use of grazing animals, the planting
of legumes on rangelands and so on - could, if
coupled with dramatic reductions in carbon dioxide
emissions, notionally add as much as 1.78 billion
tonnes of carbon from the atmosphere to soils,
lowering temperatures by 0.26 deg C. Since 1880,
global average temperatures have already risen by
about 1 deg C.
More tentatively, they suggest that if farmers added
biochar - the residue of crops burned to make
charcoal - to their soils, this could reduce global
warming by as much as 0.46 deg C.
"These are very commonly used approaches, though
people don't use them to sequester carbon - they are
doing it for other reasons", said Whendee Silver, an
ecosystem ecologist at the University of California
at Berkeley, and one of the authors.
"Any time you increase the organic content of soils,
you are generally increasing the fertility, water-
holding capacity, sustainability, decreasing erosion
and increasing general resilience to climate change.
Sequestering carbon is a side benefit," he said.
In the same week, scientists from five nations
reported in the journal Nature Sustainability that
they could show that farming practices that show
consideration for the global environment can and do
deliver more food at lower costs.
Enthusiasts and environmentalists have been promoting
"organic" or sustainable farming for decades.
They looked at data and reports from 400 sustainable
intensification initiatives - agroforestry is one
example - used on either more than 10,000 farms or
over 10,000 hectares of farmland. Altogether, their
survey covered an estimated 163 million farms.
And their study showed that productivity went up,
biodiversity and ecosystem services were conserved,
yet costs were down.
"Although we have a long way to go, I'm impressed by
how far farmers across the world and especially in
less developed countries have come in moving our
food-production systems in a healthy direction," said
John Reganold, a soil scientist at Washington State
University in the US, and one of the authors.
Reganold said stronger government policies across the
globe are now needed to support the greater adoption
of sustainable intensification farming systems so
that the United Nations Sustainable Development Goals
endorsed by all members of the UN are met by 2030.
"This will help provide sufficient and nutritious
food for all, while minimising environmental impact
and enabling producers to earn a decent living," he
said.